When sending a message using a numeric Originator (such as a mobile number), please ensure that a plus (+) is prefixed to the number prior to sending. This will ensure that the message arrives correctly to the handset and that the recipient is able to reply.
For alphanumeric Originators, please ensure that the length of the Originator is no longer than 11 characters and that it contains only letters and numbers. The ampersand (&), hash (#) and exclamation sign (!) are permitted as well
When sending a message containing a shortcode as Originator, ensure that no plus signs are added and that the length of the shortcode is only 5 characters
If a dedicated long number has recently been assigned to the account, ensure that half an hour has passed before any message send is attempted. The internal memory of the DMSP takes half an hour to refresh all numbers that belongs to messaging accounts and as such won't have any records of a new number being assigned to an account until this time period has elapsed. Once the internal memory has been refreshed the account will be able to fully utilise the number